A new survey by the Centers for Disease Control and Prevention (CDC) published in the health agency’s Morbidity and Mortality Weekly Report reveals that more than 50% of Americans are unaware how they became infected with the coronavirus.

For the multistate telephone survey, researchers contacted 350 adult hospital inpatients (23%) and outpatients (77%) who tested positive for the virus between 14 and 21 days after they tested positive for the virus. Respondents answered questions about their demographic characteristics, underlying chronic conditions, symptoms experienced on the date of testing and potential exposures to the coronavirus prior to onset of the illness.

Inpatient participants were more likely than outpatients to be older and have underlying health conditions, such as chronic respiratory disease, cardiovascular conditions and diabetes. Inpatients were also more likely to be member of a minority group and to have an average annual income below $25,000.

While both inpatients and outpatients reported a similar number of symptoms, inpatients were more likely to report difficulty breathing and less likely to report a loss of smell or taste. In addition, inpatients were less likely than outpatients to report a return to their baseline level of health at 14 to 21 days.

When asked about potential exposures, 153 (46%) of the 339 participants who provided exposure histories confirmed coming into close contact with someone diagnosed with COVID-19 during the two weeks preceding onset of the illness or the date of testing for asymptomatic patients. These close contacts were commonly family members (45%) or coworkers (34%).

Findings also showed that 64% of participants were employed, but only 17% were able to work from home. In addition, outpatients were more likely to be employed than inpatients and to have interacted with people outside their home. Interestingly, 25% of participants with a job said they worked in health care.

“These findings highlight the need for screening, case investigation, contact tracing and isolation of infected persons to control transmission of SARS-CoV-2 infection during periods of community transmission,” wrote the CDC investigators. “The need for enhanced measures to ensure workplace safety, including ensuring social distancing and more widespread use of cloth face covers, are warranted.”

For related coverage, read “Who Is Most Susceptible to the New Coronavirus?” “7 ways to Prevent the Spread of the New Coronavirus” and “Yes, You Should Wear a Face Mask to Cut Coronavirus Transmission.”

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